Emacs Lisp: Format String
(format STRING &rest OBJECTS)
-
Convert lisp objects into a string.
It takes a input string, and several other arguments of lisp objects, and output a string.
- The format control string may contain placeholders
%c
. The placeholders are replaced by argument to format. - Different placeholders means convert the argument to a string in particular way.
(format "Name: %s, age: %d" "jane" 25) ;; "Name: jane, age: 25"
;; decimal to hex. Returns 「a」 (format "%x" 10)
;; hexadecimal 「a」 to decimal. Returns 「10」. (format "%d" #xa)
- The format control string may contain placeholders
%s
-
string. Converted by
princ
. [see Emacs Lisp: Print, Output] %d
- number in decimal.
%o
- number converted to octal notation.
%x
- number converted to hexadecimal notation.
%X
-
like
%x
, but uses upper case. %e
- number in exponential notation.
%f
- number in decimal-point notation.
%g
- number in exponential notation or decimal-point notation, whichever uses fewer characters.
%c
- number as a single character.
%S
-
any object in lisp syntax (using
prin1
). [see Emacs Lisp: Print, Output]
(info "(elisp) Formatting Strings")